Mortgage Payment Calculator
/* Calculator Styles */
.seo-calc-wrapper {
max-width: 800px;
margin: 40px auto;
font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
border: 1px solid #e0e0e0;
border-radius: 8px;
box-shadow: 0 4px 12px rgba(0,0,0,0.05);
overflow: hidden;
background-color: #ffffff;
}
.seo-calc-header {
background-color: #2c3e50;
color: #ffffff;
padding: 20px;
text-align: center;
}
.seo-calc-header h2 {
margin: 0;
font-size: 24px;
font-weight: 600;
}
.seo-calc-body {
padding: 30px;
display: flex;
flex-wrap: wrap;
gap: 30px;
}
.seo-calc-inputs {
flex: 1;
min-width: 300px;
}
.seo-calc-results {
flex: 1;
min-width: 300px;
background-color: #f8f9fa;
border-radius: 6px;
padding: 20px;
border: 1px solid #e9ecef;
}
.form-group {
margin-bottom: 20px;
}
.form-group label {
display: block;
font-weight: 500;
margin-bottom: 8px;
color: #333;
font-size: 14px;
}
.input-wrapper {
position: relative;
display: flex;
align-items: center;
}
.input-prefix, .input-suffix {
background: #e9ecef;
padding: 10px 15px;
border: 1px solid #ced4da;
color: #495057;
font-size: 14px;
}
.input-prefix {
border-right: none;
border-radius: 4px 0 0 4px;
}
.input-suffix {
border-left: none;
border-radius: 0 4px 4px 0;
}
.form-control {
width: 100%;
padding: 10px 12px;
border: 1px solid #ced4da;
font-size: 16px;
outline: none;
transition: border-color 0.2s;
}
.form-control:focus {
border-color: #2c3e50;
}
.calc-btn {
width: 100%;
padding: 14px;
background-color: #27ae60;
color: white;
border: none;
border-radius: 4px;
font-size: 16px;
font-weight: bold;
cursor: pointer;
transition: background-color 0.2s;
}
.calc-btn:hover {
background-color: #219150;
}
.result-row {
margin-bottom: 20px;
padding-bottom: 15px;
border-bottom: 1px solid #e0e0e0;
}
.result-row:last-child {
border-bottom: none;
margin-bottom: 0;
padding-bottom: 0;
}
.result-label {
font-size: 14px;
color: #666;
margin-bottom: 5px;
}
.result-value {
font-size: 28px;
font-weight: 700;
color: #2c3e50;
}
.result-sub-value {
font-size: 20px;
font-weight: 600;
color: #2c3e50;
}
.calc-error {
color: #e74c3c;
font-size: 14px;
margin-top: 10px;
display: none;
}
/* SEO Content Styles */
.seo-content-wrapper {
max-width: 800px;
margin: 40px auto;
font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
line-height: 1.6;
color: #333;
}
.seo-content-wrapper h2 {
font-size: 26px;
margin-top: 40px;
margin-bottom: 20px;
color: #2c3e50;
border-bottom: 2px solid #eee;
padding-bottom: 10px;
}
.seo-content-wrapper h3 {
font-size: 20px;
margin-top: 30px;
margin-bottom: 15px;
color: #2c3e50;
}
.seo-content-wrapper p {
margin-bottom: 20px;
font-size: 16px;
}
.seo-content-wrapper ul {
margin-bottom: 20px;
padding-left: 20px;
}
.seo-content-wrapper li {
margin-bottom: 10px;
}
Estimated Monthly Payment
$1,769.77
Total Interest Paid
$357,117.20
Total Cost of Loan
$637,117.20
function calculateMortgage() {
// 1. Get Input Values
var homePrice = parseFloat(document.getElementById('mc-home-price').value);
var downPayment = parseFloat(document.getElementById('mc-down-payment').value);
var interestRate = parseFloat(document.getElementById('mc-interest-rate').value);
var loanTermYears = parseFloat(document.getElementById('mc-loan-term').value);
var errorDiv = document.getElementById('mc-error');
// 2. Validate Inputs
if (isNaN(homePrice) || isNaN(downPayment) || isNaN(interestRate) || isNaN(loanTermYears) ||
homePrice <= 0 || interestRate < 0 || loanTermYears = home price
if (principal <= 0) {
document.getElementById('mc-result-monthly').innerText = "$0.00";
document.getElementById('mc-result-interest').innerText = "$0.00";
document.getElementById('mc-result-total').innerText = "$0.00";
return;
}
var monthlyRate = (interestRate / 100) / 12;
var numberOfPayments = loanTermYears * 12;
var monthlyPayment = 0;
// If interest rate is 0, simple division
if (interestRate === 0) {
monthlyPayment = principal / numberOfPayments;
} else {
// Standard Mortgage Formula: M = P[r(1+r)^n]/[(1+r)^n-1]
var mathPow = Math.pow(1 + monthlyRate, numberOfPayments);
monthlyPayment = principal * ((monthlyRate * mathPow) / (mathPow – 1));
}
var totalCost = monthlyPayment * numberOfPayments;
var totalInterest = totalCost – principal;
// 4. Update Output Results
// Helper function for currency formatting
var formatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
minimumFractionDigits: 2,
maximumFractionDigits: 2,
});
document.getElementById('mc-result-monthly').innerText = formatter.format(monthlyPayment);
document.getElementById('mc-result-interest').innerText = formatter.format(totalInterest);
document.getElementById('mc-result-total').innerText = formatter.format(totalCost);
}
Understanding How Your Mortgage Is Calculated
Calculating your monthly mortgage payment is a critical step in the home-buying process. While the math can seem complex, understanding the components of a mortgage loan helps you determine exactly how much house you can afford. Our Mortgage Payment Calculator breaks down the financial equation into simple terms, allowing you to see the impact of interest rates, down payments, and loan terms on your monthly budget.
The Core Components of a Mortgage
When you take out a loan to buy a home, your monthly payment is primarily determined by four key factors:
- Principal: This is the amount of money you borrow from the lender. It equals the home purchase price minus your down payment.
- Interest Rate: The cost of borrowing money, expressed as an annual percentage. Even a small difference in rates can significantly affect your total payment over 30 years.
- Loan Term: The duration of the loan. The most common term is 30 years, though 15-year loans are also popular for those who want to pay off debt faster and save on interest.
- Down Payment: The upfront cash you pay toward the home. A larger down payment reduces your principal and typically lowers your monthly payment.
How the Calculation Works
Mortgages generally use an amortization formula to determine equal monthly payments over the life of the loan. In the early years of your mortgage, a large portion of your payment goes toward paying off interest. As time passes, the balance shifts, and more of your payment is applied to the principal balance.
The standard formula used by lenders is:
M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1 ]
Where:
- M = Total monthly payment
- P = Principal loan amount
- i = Monthly interest rate (Annual rate divided by 12)
- n = Number of payments (Loan term in years multiplied by 12)
Strategies to Lower Your Monthly Payment
If the calculated monthly payment is higher than your budget allows, consider these strategies to reduce costs:
Increase Your Down Payment: Putting down 20% or more not only lowers the principal amount but also eliminates the need for Private Mortgage Insurance (PMI), which is an extra fee charged to borrowers with smaller down payments.
Improve Your Credit Score: Borrowers with higher credit scores often qualify for lower interest rates. A difference of just 0.5% in your interest rate can save you tens of thousands of dollars over the life of the loan.
Choose a Longer Loan Term: Extending your loan from 15 years to 30 years will lower your monthly payment, although you will end up paying more in total interest over the long run.
Why Total Interest Matters
Many homebuyers focus solely on the monthly payment, but the Total Interest Paid metric is equally important. This figure represents the true cost of borrowing. By using the calculator above, you can see how adjusting your term or making extra payments can drastically reduce the amount of money you give to the bank, helping you build equity in your home faster.